Over 8,500 migrants reach Spain's Canary Islands in two weeks -ministry data

MADRID (Reuters) - At least 8,561 migrants have reached the Canary Islands over the past two weeks, representing more than a third of this year's total arrivals, data from Spain's interior ministry showed on Monday.

Between Jan. 1 and Oct. 15 of this year, the islands in the Atlantic received 23,537 migrants, an 80% increase from the same period last year, the data showed.

The archipelago's seven islands have become the main destination for migrants from Senegal and other African countries trying to reach Spain. Others seek to cross the Mediterranean to the Spanish mainland.

Milder weather and calmer seas in September, October and sometimes November usually trigger an increase in migrant arrivals.

According the European Union's border agency Frontex, political instability in Senegal was also acting as a "push factor" driving people to leave the country via the West Africa route.

Spain has voiced concern over the increase in irregular migration this year, saying it cannot cope without help from the EU.

Acting Interior Minister Fernando Grande-Marlaska visited the archipelago on Monday and said the country would deploy two additional planes to help monitor migration routes.

One aircraft will patrol the waters off Senegal and Mauritania and a second will monitor the waters around the Canary Islands.

The Canaries, which lie around 100 km (60 miles) off Africa's west coast, had their highest peak of migrant arrivals in 2006, when almost 32,000 migrants reached the islands as other routes to Europe were blocked off.

The Atlantic migration route to the Canary Islands, typically used by sub-Saharan African migrants trying to reach Spain, is one of the world's deadliest.

(Reporting by Emma Pinedo; Editing by David Latona and Christina Fincher)